This invention relates to a device for oxygenating blood in an extracorporeal circuit.
During surgery, blood flows through extracorporeal circuits. The extracorporeal circuits include an oxygenation device to transfer oxygen to the blood received from the patient by means of a line which is known as venous line and then return it to the patient by means of a line known as arterial line.
The structure of the oxygenator is such as to delimit a portion of space which contains capillaries made of microporous membrane which convey oxygen and are wet externally by the blood that flows through this portion of space. There are also oxygenators which include a heat exchanger through which the blood is meant to flow before entering the oxygenator in order to be kept at the correct temperature.
Often on the arterial line there is a filter (the arterial filter), which is meant to retain any air bubbles present in the blood in order to prevent them from remaining in the blood that returns to the patient. However, this presence can be the source of problems for operators when one considers the inherent complexity of the extracorporeal circuit in which the arterial filter is introduced.
The aim of the present invention is therefore to provide a blood oxygenation device in which the extracorporeal circuit is simplified and which offers maximum safety in preventing air bubbles from being contained in the blood that returns to the patient.
The proposed aim is achieved by a blood oxygenation device comprising a first structure suitable to delimit a portion of space which contains capillaries made of microporous membrane. The capillaries convey oxygen and are wet externally by blood flowing through the portion of space between an intake connector, which is connected to the venous line of the extracorporeal circuit, and a delivery connector. There is a second structure monolithically connected and contiguous to the first structure suitable to contain blood filtration means which divide the portion of space delimited thereby into a blood distribution chamber, provided with an air vent and connected to the delivery connector of the first structure, and a blood collection chamber which is provided with a delivery connector which is connected to the arterial line of the extracorporeal circuit.
In one aspect, this invention is a device for oxygenating and filtering blood in an extracorporeal circuit comprising a housing defining first and second interior chambers, the first chamber containing a plurality of microporous filters and having a blood inlet and a blood outlet connected to the first chamber to define a blood flow path along an exterior of the hollow fibers and having a gas inlet and a gas outlet connected to the first chamber to define a gas flow path through the lumens of the hollow fibers, the second chamber containing a filtration membrane and having a blood inlet and a blood outlet connected to the second chamber to define a blood flow path through the filtration membrane, the blood inlet of the second chamber being connected to receive blood from the blood outlet of the first chamber.
In a second aspect, this invention is an integrated device for oxygenating and filtering blood in an extracorporeal circuit, comprising an oxygenator having a housing including a top, a bottom, and a side wall together defining an oxygenation chamber containing a microporous membrane, the housing having a blood inlet and a blood outlet positioned to define a blood flow path along a first side of the microporous membrane and a gas inlet and a gas outlet positioned to define a gas flow path along a second side of the microporous membrane; and an arterial blood filter having a housing including a top and bottom, a substantially cylindrical outer wall, and a substantially cylindrical inner wall together defining a substantially ring-shaped interior chamber containing a filtration membrane, the inner wall defining a substantially cylindrical opening in the housing of the arterial filter, the housing having a blood inlet connected to the interior chamber on a first side of the filtration membrane and a blood outlet connected to the interior chamber on a second side of the filtration membrane, to define a blood flow path through the filtration membrane, the blood inlet of the arterial filter being connected to the blood outlet of the oxygenator, the housing of the oxygenator being rigidly connected to the housing of the arterial filter and positioned in the substantially cylindrical opening in the housing of the arterial filter.
In a third aspect, this invention is an integrated device for use in an extracorporeal blood circuit, comprising a housing defining a first portion and a second portion; means for oxygenating blood contained within the first portion of the housing, the oxygenating means including a blood inlet and a blood outlet; and means for filtering oxygenated blood, the filtering means having a blood inlet connected to receive blood from the blood outlet of the oxygenating means and a blood outlet.
In a fourth aspect, this invention is a monolithic device for use in extracorporeal blood circuit, comprising a housing having a blood oxygenator portion and an arterial blood filter portion, the blood oxygenator portion containing a gas exchange membrane and having a blood inlet and a blood outlet defining a blood flow path along a first side of the gas exchange membrane and having a gas inlet and a gas outlet for defining a gas flow path along a second side of the gas exchange membrane, the arterial blood filter portion containing a filtration membrane and having a blood inlet and a blood outlet defining a blood flow path through the filtration membrane, the blood inlet of the arterial blood filter portion being connected to receive blood from the blood outlet of the blood oxygenator portion.
In a fifth aspect, this invention is an arterial blood filter comprising a housing having a top surface, a bottom surface, a substantially cylindrical outer wall and a substantially cylindrical inner wall together defining a substantially ring-shaped interior chamber, the inner wall defining a substantially cylindrical opening from the top surface to the bottom surface of the housing; a filtration membrane contained within the ring-shaped interior chamber; a blood inlet; and a blood outlet, the blood inlet and blood outlet being positioned on the housing to define a blood flow path through the housing across the filtration membrane.